Otto-von-Guericke-University, Institute of Instrumental and Environmental Technology, Department of Systems Engineering and Plant Safety, Universitätsplatz 2, 39106 Magdeburg, Germany.
Otto-von-Guericke-University, Institute of Instrumental and Environmental Technology, Department of Systems Engineering and Plant Safety, Universitätsplatz 2, 39106 Magdeburg, Germany.
J Hazard Mater. 2016 Apr 15;307:302-11. doi: 10.1016/j.jhazmat.2016.01.018. Epub 2016 Jan 12.
The risks associated with dust explosions still exist in industries that either process or handle combustible dust. This explosion risk could be prevented or mitigated by applying the principle of inherent safety (moderation). This is achieved by adding an inert material to a highly combustible material in order to decrease the ignition sensitivity of the combustible dust. The presented paper deals with the experimental investigation of the influence of adding an inert dust on the minimum ignition energy and the minimum ignition temperature of the combustible/inert dust mixtures. The experimental investigation was done in two laboratory scale equipment: the Hartmann apparatus and the Godbert-Greenwald furnace for the minimum ignition energy and the minimum ignition temperature test respectively. This was achieved by mixing various amounts of three inert materials (magnesium oxide, ammonium sulphate and sand) and six combustible dusts (brown coal, lycopodium, toner, niacin, corn starch and high density polyethylene). Generally, increasing the inert materials concentration increases the minimum ignition energy as well as the minimum ignition temperatures until a threshold is reached where no ignition was obtained. The permissible range for the inert mixture to minimize the ignition risk lies between 60 to 80%.
在处理或加工可燃粉尘的行业中，仍然存在与粉尘爆炸相关的风险。通过应用固有安全（缓和）原理，可以预防或减轻这种爆炸风险。通过向高可燃材料中添加惰性材料，可以降低可燃粉尘的点火灵敏度，从而实现这一目标。本文介绍了在实验室内，研究添加惰性粉尘对可燃/惰性粉尘混合物的最小点火能和最小点火温度的影响。实验分别在哈特曼装置和 Godbert-Greenwald 炉两种实验室规模设备中进行，以测试最小点火能和最小点火温度。通过混合三种不同的惰性材料（氧化镁、硫酸铵和沙子）和六种可燃粉尘（褐煤、石松、墨粉、烟酰胺、玉米淀粉和高密度聚乙烯），可以实现这一目标。通常情况下，随着惰性材料浓度的增加，最小点火能和最小点火温度都会升高，直到达到一个无法点火的阈值。为了将点火风险降至最低，惰性混合物的允许范围在 60%至 80%之间。
